Why Do They Build On The Flood Plain?

15 years ago, when we had dial up, Dr Desert Flower and I bought Monkey Puzzle's "Joie de Groissant" album on CD. I still love CDs, and have not embraced DDF's old 4 gig discarded Ipod, preferring instead to rotate CDs in an out of my car, office, and living room CD players. No genius mixes or shuffles necessary, just a little laser is all.

The 2nd song on Joie de Groissant is "Flood Plain". I've searched and searched on Google, and I cannot find the lyrics posted (from dial up days perhaps). So I will post them here:

Trees torn from their roots, roads washed away, leaving no escape
wrestled free fences lay flatten by the river, rolling in waves
verdant fields they file down in shadows deep and spilling over the threshold of our home
this life we've built is drowning in too much of a good thing

WHY? Why did we build on the flood plain?
WHY? Why did we build on the flood plain?
WHY? Why did we build on the flood plain?

We built our home on this low land so we knew we were tempting fate
We ignored our old gramps warnings, 'cause we really loved this place
I guess we loved its lushness, it seduced us with its promise, that everything we planted here would grow
But now our crops are drowning is it time to let them go?

WHY? Why did we build on the flood plain?
WHY? Why did we build on the flood plain?
WHY? Why did we build on the flood plain?

Now, are we sinking back down?

I bring this up, because as we drove around the NE Phoenix valley, we kept passing over this apparently superfluous earthen dam. It tries to wall off the northern valley from some massive invasion of water from Flagstaff perhaps, but pesky things like bridges and overpasses keep penetrating it (here). Apparently, there was some post-deluvian reaction to build a 20 foot high wall when the northern valley was inhabited by Saguaros, jack rabbits, and citrus groves. Maybe they were expecting a massive deluge that's never arrived?

If there was truly a risk of a flood, then shouldn't there be flood gates at each of the road crossings that penetrate the wall.? Googling the "Phoenix Flood" or "Great Phoenix Flood" yielded something interesting though. There's been some massive floods of limited areas - the Gila River and Salt Rivers over-flowing, a small spot up near the mountains around Safford AZ received "1,740 cubic feet per second" in 1974. In the 80s, the Salt River (which runs beside the PHX air port) was 2 miles wide and flooded most of down town through the Cave Creek tributary.

So history has shown at the entire Phoenix valley (Tempe, Mesa, Glendale, Phoenix, Scottsdale) lays within a 100 to 500 year flood plain, theoretically (FEMA links here and here). Since the floods of the 70s and 80s, the state of Maricopa has implemented wide spread spill ways and flood control in all new construction, so such severe flash floods as they had in the 70s are much less likely. The Adobe Dam on the north side of town was built in 1980 to attempt to protect Phoenix from a flooding of Skunk Creek north of town... I just hope that it never rains so much here (or sea levels rise hundreds of feet - link here and here) to flood my home that is at 1100 feet elevation. Of course Roosevelt Dam breaking, 50 miles east of town, would have cataclysmic results for the entire valley, now that it is full of water.

Having evolved in a generation that debuted Red Dawn, The Day After, Omega Man, Escape From New York, Death Race 2000, the 3 Mad Maxes, Threads, the Terminator, and reading Larry Niven's Lucifer's Hammer, Larry King's The Stand... I figured that someday, 'when I grew up' I'd need to
- have a home on the back side of a mountain a few miles outside of a major metropolitan area, to guard against the 1 mile high detonated thermonuclear warheads tipping Russian ICBMs.
- have no one up hill of me, so that there was a clear field of fire to take out marauding zombies, hordes of post-apocalyptic cannibals, invading Cubans, and others who would want to do me harm who were capable of climbing any higher ground
- keep enough sturdy raw materials, fasteners, and a single phase welder on-hand to be able to fabricate impromptu armor plating and bracketry
- store up enough provisions to ride out 2 years of nuclear winter (but I'm not LDS, so in AZ it's kind of strange to try and do so)
- be well armed, and up to date on weapons training
- maintain a working electrical generator, capable of powering my home
- secure an adequate water supply (12,000 gallons of pool, that could be covered / protected from fallout or pillaging, and made potable)
- not live in the flood plain

I've got the last 4 covered (from a 100 year flood, but I'd like to get to the 500 year level, as the Indus River just had). Now I need to work on the first 4. It's not something that I'm actively developing everyday... but it Is always in the back of my mind. =)